flint



F. F. FLINT A a-i130, 1929.

CARBURETOR Fil ed Sept. 14, 1925 2' Sheets-Sheet u l F. F. FLINT April 30, 1929.

CARBURETOR 26 Fig 9 M W35 2, 1 v. m w 1 1.1.1 w/ 1 1 1 O 0 1 J 9 2 1 0a 1 T 5 w 10 bu'retor.

tion or FLOYD nrnrnr', or nn'rnorr, vrrcnrenrr, nssrenonor ONE-HALF r MAXWELL w.

. BENJAMIN, on nnrnorr, MICHIGAN,

onniz'onn'ron.

This invention relates to carburetors such are used in connection With automobile en gines and other internal combustion engines.

' l in the ordinary carburetors commonly used inauto mobiles, the mixture of air and light hydrocarbonvapor is regulated in its proporthis being usually a needle'valv'e, controlling the supply-or" ,fiuid hydrocarbontothe car- This adjustment is a manual adjustment, and when once made is usually kept in its adjustedcondition since any changein the adjustment is diliicult to make with accuracy and requires considerable time, even 1 though theconditions prevailing may differ to a veryconsiderable extent. For-instance, economyin the consuinptionof the hydronot economical for high speed running since theproportion of hydrocarbon for slow speed running is necessa ly in excess of the proportion required for high speed running. Consequently; when running at high speed With such an adjustment, the fuel uscd is much i more than is essentialto obtain the proper resultsf One lil'll'mltiln't object of the present inven .tion is to provide an improved "form of carburetor whereint'herewill be efiected' an au toinatic adjustment ofthe proportions of air 1 and fuelfthis adjustment being in accordance with compensating forthe difference in conditions due to such elements in the opera- 'tcrnal combustion motors as variations in "speed; variations in barometric pressure, and in tact, substantially all of I the variations that occur in running engines ofthis type- Again, it is 'very frequent in automobiles tl'iat a vacuum system is used to supply gasoline to the carburetor. I Use of such a system entails a vacuumftank located above the car buretor so thatthe liquid hydrocarbon may flowfromsuch tank to the carburetor by grav-ity and'a more'or less complicated system of pipe connections to: ensure a vacuum tions by the adjustment of a certain valve,

being naint'ained in such a tank. With such an. arrangementany defect in the maintenance of the vacuum results in a cessation or inell'ective operation of the system with the consequence that the carburetor is insufficiently'supplied with the liquid fuel, and the operation of the engine either ceases or is deleteriously affected.

A second important object ofthe invention is to provide an improved construction of carburetor wherein the operation Will be effected by a partial vacuum maintained in one portion of. the carburetor structure itself, thus eliminating all special vacuum tanks and their connection. I

The usual type of carburetor is provided Witha fixed Venturi tube, that is to say, the relative position of the Venturi tube and the jet nozzle for the liquid hydrocarbon are fixed so-that when once in position this position is maintained throughout the life of the oar ,buretor. .Efiorts have been made to overcome the disadvantages resulting from a fixed venturi tube by the employment of Ventur1 tubes, the position of which may be varied (along'the nozzle by the difie'rences in pres- "sure at opposite ends of the tubes,'the movement being resisted'by springs or the like.

- Tl1GS=d eliorts have been found-ineffective for the-purpose desired; and a third important ob ect of the present invention isto provide a carbure having a freely floating p Ven turi tube so arranged that its movement controlsthe richness of the explosive*mixturc in hydrocarbon.

' Other iniportant objects of the invention,

struct-ion is such that in the event of a breakage in the supply tank, or the line leading thereto an auxiliaryfsupply may be quickly adjusted; to provide an improved form of carburetor wherein suflicicnt explosive mlxture will at all times beavailableuto permit VJith the above and other objects in view I are to provide a carburetor wherein the con- I r as' villbe hereinafter apparent the invention consistsintgeneral ofcertain novel details of "construction and combinations of parts her'einafter more fully described, illustrated in the accompanying drawings and specifically claimed.

In the accompanaying drawings like cliaractors of reference indicate like parts in the several views, and:

Fig. 1 is a plan view of the complete carburetor. Fig. 2 is aside elevation thereof.

Fig. 3 is a section on the line 33 of Fig. 1. 4: is asection on the line 44: of Fig. 1. I Fig. 5 is a section on the line 55 of Fig. 2. The present en'ibodiinent of the invention,

' as shown in the drawings, illustrates one preferred form thereof, but it will be understood that the principles iiwolved may assume in actual practice, a variety of forms, and this embodiment .is to be understood as merely to show one of such forms, the invention not being confined tothe particular form and proportions herein illustrated.

In this embodiment there is provided a hollow bottom 10 'constitutin g a reservoir; This bottom is of elongated form and at one end thereof there is superimposed on the bottom a float chamber 11. This fleat chamber 11 i consists of a cylindrical tube 12 forming the side wall thereof, this tube being seated on a gasket 1.3 and having a top 14L closing the upper end; The tube is held on the gasket and the top on the tube by means of suitable studslii, which. extend through the top and .into the top of the reservoir 10. The top of the reservoir 10 is provided, centrally of the tube 12, with an opening 16 wherein is seated a housing '17 having a valve casing 18 pro .jecting from one side.

In this valve casing i s-fitted a poppet valve 19 which opens from v v the chamberll inwardly to the reservoir 10 tion. closed by a pipe connection 31 to which is counected the gasoline supply pipe 32 leading at certain times during the operation and closes communication between the float chanibtll' and reservoir at other times.

centrally of the housing I? and. depending from the top thereof is a valve stem guide 20, the lower end of the vertically ll'lOVflblG valve stem 21 having fixed thereon al'ower collar 22, and an. upper collar 23 in spaced relation. Above the upper collar 23, the valve stem carries a valve 2 Which serves to close the lower end of a suction pipe 25 screwed through the top 14:. Screwed into one side I of the top is a pipe T 26 having its upper end closed normally by a plug 27. To this pipe T connected a casing 28 containing an upwardly opening check valve 29 in its upper portion, and a strainer 30 in its lower por- The lower portion of the casing 28 is from the usual gasoline tank (not shown). At 33 is the float, and leading from the top 31 4 downwardlythrough this float and open- ='iiig.into.tlie housing 17 is a vent tube 34, the

venttube'having a slight clearance at the top,

as shown at 35. In other words, theveiit Located.

tube does not fit tightly in the top 14, but

permits air to enter around it. *xtending upward from the upper end of the housing is a cai'bureting chamber 36, surrounded on its side by a jacket 3'? and having at its top a flange 38 for connection to the intake manifold of the engine.

diameter to provide a shoulder so as to limit the downward movement of a Venturi tube 39 mounted to slide-freely in the carbureting chamber between said shoulder and stoo ring 40 fixed at the proper point above the Venturi tube. Extending upwardjinto the carbureting chamber through the top of the reservoir ltlis a jet tube or nozzle 41 whiciiterminates close to the bottom of tl e chant her 10. The pipe 25 is connected to the upper part of the chamber 36 by means of a pipe connection 42 opening into said chamber 36 above the usual butterfly valve 43.

Extending up from the top of the reservoir 10 between the chamber 36 and tube 12 is a tubular housing 4:4: through which passes a second ettube 45 opening into a lateral, passage as communicating with the interior of the chamber 36 by. a short tube 427 Which passes through the jacket space 3?. The outer end of thischainber l6 is'closed by 'a plug being located in saidchainber andserving to seat on the valve during certain periods of the operation of the deviceso as to prevent any back pressure from the chamber 33pm?- ing through the pipe connection42. At the lower part of the chamber 36 thereare 'pro vided ceii'tain airports 53,'which aire forn'ied by tubes passing threugl'i the jacket space 37 and opening outwardly under. a rotating sleeve 54; having corresponding openingst'ifi The lower end of the car-' bureting chamber 36 is reduced slightlyin lJU formed therein, the sleeve being shittable circuinferentially around the chamber 36 tocoiitrol the admissienof a' 'to the lower part of said chamber.

In the operation of the device,"let itbe supposed that the carburetor has'been con 1 nected up to the gasoline tank and the intake nanifold, andthat no gasoline is in the car- "buretor. In starting, the operator steps on.

his starter which 0 5 course results in turning his produces a 'SUCtIOn 111 Y the engine over. the upper part of the-chamber 36, tlie'butterfly valve being'closed. Consequently, a

partial vacuum is produced in the chamber 11, and th s. starts the gasoline from the tank throughthe-pipe 32, past the valve throughthe pipe connectionxQG, from whence l s it passes into thechamber 111 1 It s 'to be understood that the clearance at 35 is of such slight degree, that the incoming air at this point does not interfere with suiiicient vacuum being produced to cause the gasoline to pass from the tank in the manner described.

As the gasoline rises in the chamber 11, the

head produced opens the valve 19 and it flows past this valve into the reservoir After vfilling the reservoir it rises inthe' housing tube le, and at the sametime the float 33 rises until itengages the upper collar 23 whereupon it hits the vvalve 24 and closes vthe lower end of the pipe connection cutting oii the vacuum. The .valveu2l' then remainsclosed until the gasoline drops in the chamber 11 sufficiently to bring the float 00 into contact with the lower collar 22 whereupon the weight of the float and the valve 24: and its stem collars will act to again open the'pipe connection 25' and the operation is again repeated. Now so long as the butterfly valve 4-3 remains closed, gasoline will flow up through the jet pipe under the influence of the suction strokes of the engine, and will pass into the upper part of the chamber 36Vabove the butterfly valve. In

order to provide for sufiicient airto make an explosive mixture with this gasoline, a vent 56 opens into the chamber 46, and is controlled by an ordlnary 1 needle valve 57.

Under these conditions, the explosive mixture will be reachedin hydrocarbon and the engine will start, and so longlasthe butterfly 7 through the'pipe 34, and in order to prevent valve is closed, willfidle or run slowly.

it is well known fact that whenever an engine s stopped after running and; the

crank shaftr'o cks back andi'orth to a certain degree, this causes a certain amount of back pressure at thetiine when the inlet valves are openg This back pressure, ifnotprevented from reaching the chamber 11 would cause pressure in that chamberwith the consequence that the gasoline would be ejected this, the valve 52 is provided. The action 0t this valve is that whenever this back pres sure takes place in the manner described, the 'valve 52 promptly closes and thus no presureis exerted inthe chamberll or the reservoir 10. I

When it is desiredfto increasethe speed of the engine the butterfly valve is opened in .the'manner common to ordinarycarburetors. Upon the opening of-this valve, the suction in the chamber 36 draws-gasoline through the jet tube ll. Now, dependent on the speed at which the engine is running, the Venturi tubewill assume ai pG SltlOn between the shoulder in the lower part of the chamber 36 and the ring 40. This movement of the Venturi tube automatically maintains the )roner ratio bet-ween the fuel va or and air at all stopspeeds. This ratio is maintained without any alteration in the setting of either the sleeve l orthe butterfly valve4-3. In

order to understand this, an example may be given- Suppose the automobile carrying this carburetor 18 running along level ground.

Also sun 305% the s Jeed to be in the nei hbor- 1 hood of forty miles per hour. Now the Venturi tube 39 under these conditions will have risen until the proper proportion of air and fuel vapor is obtained. Upon the automobile reaching a hill, the conditions due to hill climbing will cause a slowing down of the speed, and byreason of this drop in the speed, the Venturi tube 39 will tend to fall toward the bottom of the chamber 36. This downward movement of the Venturi tube results in increasing the velocity of air at the tip or nozzleof the jet tube ll, and consequently increases the proportion of gasoline mixed with, the air, thus enriching the mixture so that additional power is given in climbing the hill. \Vhen the top of the hill engine in cool weather, it is sometimes advisable to close or'partially close these ports until the engine 1S heated up whereupon the sleeve may be restored tolts running position.

a lug 58 which is suitably connected by a reach rod (not shown) to a handleror the like on the dash of the machine. Similarly the but- 'teriiy valve is likewise provided withmeans for operationirom the dash, thevalve having a stem 59 carrying a lever 60"adapted to be connectedby a rod with a suitable operating'handle on the dash. The jacket 37 is provided with an inlet connection (ilwhich communicates by su table pipe-connection including a shut-oil with the exhaust, this pipe connection, and the shut-oil not being deemed-necessary here to be shown, as they are of ordinary construction. Also the acket is provided with an outlet connection 62.

Plugs 63 are provided in the bottom or the reservoir 10 to permit "access to the jet tubes 41 and 45 for. change or renewal of these parts and the bottom of the reservoir is also provided with a drain cock 64 of ordinary type in order that the gasoline may be drained therefrom when desired This drain cock also affords means for definitely ascertaining whether the carburetor contains gasoline.

It will be observed that the shut-oil to the jacket connection is for the purpose of regulating the temperature of the instrument,=it being obvious that the greater the quantity of thehot exhaust gases which are allowed to pass throughthe jacket, the hotter the cham- 'Now this sleeve is provided on one side with i the chamber 11. Thus with the three methodsher 86 becomes, and that the opposite is true.

It will be further noted that it is the intent of the invention to have the jacket 37 of such size that not only will the heat from this jacket provide heat for the chamber 36 but it will also be suflicient to heat the gasoline in thereservoir 10 and thus heat the entire instrument, thus enabling the more effective vaporization of the gasoline. Furthermore, the construction is such that the air entor ing the lower part of the chamber 36 is warm while the gasoline passing through the jet tube 41 is hot. The mixture which takes place at themouth oi the Vcuturi and tubes then cools ofl to a 0 .stain extent, and entering the engine is of course heated by the heat of the engine itself and the action of compression thus refining the mixture and causing a better combustion.

Reference has been made to a plug 27 in the top of the'pipe connection 26; With this instrument in the event of any cessation of flow through the pipe 32 such as maybe caused by the rupture of the gasoline supply tank, or the breaking of this pipe, orthe clogging of the same does not necessarily stop the operation of the carburetor, because the plug 27 may be removed and the ordinary tube, such as a rubber pipe may be connected to the pipe fitting 26 at this point, and its other end may be connected toany suitable source of supply, such as a can of gasoline, or a bucket of gasoline, or any other container whereupon the instrument will operate pre cisely in the same manner as before. Fur; thermore, ifthe vacuum system herein contained should for any cause fail, connection may be made through the pipe connection 26 as before and gravity teed used. For instance,the1uibber pipe referredto might be used to siphon the gasoline from a bucket to otproviding gasoline teed to the chamber 11,

the continued operation of the vehicle is assi'lred sojlong as gasoline can be obtained to food the ch ainber 11.

There has thus been. provided a hi ghly cient deviceot'the kind described and or the 7 purpose specified.

It is obvious that minor changes may be made in the form and construction of the invention without in any way departing from municationwith the atmospheric air above the level at which the fuel stands in the float chamber, and a mixing chamber supported on the other end oi the reservoir and having communication therewith.

2. In a carburetor,-a reservoir forming abase, a float chamber on top of said reservoir having a minute orifice in the top affording constant communicationwith the outer air, the capacity of the reservoir being substantially greater than the normal fuel content of the float chamber, said float chamber having valve controlled communication with v the reservoir, said reservoir 'having'free com-' munication with the atmospheric air above the level at which the fuel stands in the float chamber, a mixing chamber. supported on the other end. of the reservoir and having communication therewith, and pipe communication between the upper end of the mixing chamber and the top of the float chamber whereby the valve communication is held closed under predetermined conditions of fuel level in the float chamber.

8. Ina carburetoryfa fuel reservoir forming a base and having suflicient capacity to permit operation of the carburetor for a; considerable time without additional fuel entering-the reservoir, afloat chamber on one endof the reservoir. and having communi cationtherewlth, a check valve controlling the flow oi": fuel tosaid reservoir and opening toward .the reservoir, a mixing chamber at the other end of the reservoir and com-'- inu'i iicating therewith, apipe con'nnunicz. .1021 between the'top of the float chamberand the mixing chamber and arrangedto pro duce pressure effects in the float chamber whereby tocontrol opening and closing of said check valve, said reservoir having nee;- comniumcationwith the atmospheric air at a point above the level at which the fuel stands in the float chamber.

In. testimony whereof I atiix'mysignature.

FLOYD F. FLiuT. 

